The present invention relates to compliant electrical connectors for making spring-biased electrical contact between mating electrical connectors, particularly "high cycle life" connectors that are repeatedly connected and disconnected during use. The invention provides a high reliability connector that can be connected and disconnected for thousands of cycles without adversely affecting the electrical integrity of the connection. The invention also is characterized by inexpensive means for making various embodiments of these high cycle life, high reliability compliant electrical connectors.
The compliant connectors of this invention can be used in any of numerous portable applications involving mating electrical connectors subject to repeated use. Many prior high cycle life connectors are subjected to strong wiping action during use. This can lead to excessive wear and resulting unreliable connections. Many of these connectors have a compliant element for retaining spring pressure contact during use. Certain compliant connectors do not have long term reliability. For instance, in some connectors the compliant element is provided by compressible rubber blocks or conductive rubbers that take a set and thereby experience loss of necessary compliancy during use.
The present invention does not relate to the familiar electrical plug and receptacle connectors in which fixed (non-movable) connectors projecting from a plug are inserted into cooperating electrical receptacles in the mating connector. The connectors of this invention are of a type in which one connector has movable solid metal contact pins that make compliant surface contact with fixed electrical terminals on the mating connector. These terminals on the mating connector are not the receptacle type, but rather, comprise surface contact terminal means such as protruding solid metal pins, flat solid metal pads, or thin metal circuit traces on either printed circuit boards or on flexible carrier films referred to in the art as "flex circuits." The compliant connector of this invention has contact pins that make releasable spring-biased surface contact with the fixed contacts or conductors on the mating connector. These compliant connections retain their electrical contact integrity sufficiently to ensure continuous reliable electrical contact during use. The invention is particularly useful in maintaining high reliability compliant connections in high vibration environments.
As mentioned, the compliant electrical connectors of this invention can be used for a wide variety of applications involving repeated connecting and disconnecting of the connector from a mating electrical connector. One use of the invention is for a battery pack installed on a cellular telephone for producing good spring-biased contact between the pins of the connector and the terminals on the battery pack. Similar uses include batteries that may be used in any electronic or electrical device that operates on batteries requiring frequent removal and reinstallation. Other uses of the connector can include portable electronic notebooks for connecting to removable memory modules that plug into the notebook, lap top computers for plugging into a computer docking station, or various electronic devices that are inserted into a battery charger for electrically connecting the electronic device to the recharger. In some applications, the invention can be used where high reliability interconnections of mating printed circuit boards are required. The connector also is useful in environments subject to high vibrational forces during use, and one such use of the connector is for making reliable electrical connections between an ink-jet cartridge and an ink-jet printer.